Vala language support in Atom

Add syntax highlighting and snippets to Vala files in Atom.

Forked from the language-vala
package, the main difference is that this package is more actively maintained.
If you use the language-vala package you will find that it does not
automatically syntax-highlight Vala files. This package does, as it includes the
scopeName field in its grammars/vala.cson file.

I think this package is bad news.

Good catch. Let us know what about this package looks wrong to you, and we'll
investigate right away.